The Rocket Factory: SpaceX Builds Them From Top to Bottom

The commercial space race is about to begin. Early Saturday morning at 4:55 a.m. EDT, the first privately designed and built spacecraft destined for the International Space Station is expected to lift off from the historic Cape Canaveral Air Force Station not far from the Atlantic Ocean on Florida's east coast. The Falcon 9 rocket and Dragon capsule are designed and built by Space Exploration Technologies -- the company better known as SpaceX -- at the company's factory not far from the Pacific Ocean in Hawthorne, California.

Tomorrow's scheduled launch puts an exclamation point on a new era of space transportation. If the first era of space flight focused on a Cold War-driven race to show what could be done, and the second era focused on making space flight and delivering orbiting payloads routine, this new era is focused on making all of the above a lot less expensive.

SpaceX is leading the charge to bring down the cost of flying to space. Driven by a personal desire to make life multi-planetary -- aka travel to Mars -- the company's founder and leader Elon Musk has built a program with about $4 billion worth of contracts and launch orders already on its books. But it has only launched a few customer payloads so far.

With just a handful of launches under its belt, SpaceX has yet to successfully prove its business case of dramatically reducing the cost of delivering payloads into orbit. And both its founder Elon Musk, and current customer NASA, rarely miss an opportunity to emphasize the challenging nature of the upcoming ISS mission. But the company is on target for backing up its low cost promise and is managing to achieve this goal by spending hundreds of millions, rather than billions of dollars.

Musk honed his business skills in the internet startup arena of the late 1990s. He makes no secret that one of the keys to reducing the cost of space flight is operating an efficient company that is nimble and lacks the bloated layers that exist in many of the large, veteran aerospace companies that have been building rockets and spacecraft for the past 50 years. SpaceX has received large investments from private sources -- including a hundred million from Musk himself -- as well as funding from NASA. But the company operates more like a lean startup despite the fact it should soon overtake Russia as the number-one producer of rocket engines in the world.

Like at most startups, employees often wear multiple hats. Engineers, including Musk, work in an office-free open cubicle layout less than a minute's walk from where technicians are building rocket engines and machines are welding together space capsules. Leave your desk, walk past a conference room, open a door and you step into a giant rocket factory. Actually the first thing you walk past on the factory floor is open floor space that is the cafeteria, which is right next to the mission control room, then a few steps after that you walk by the rocket engine assembly line.

During lunch you can watch the software team rehearsing the upcoming mission to the ISS a few feet away to your right. You can hear the construction of aluminum-lithium being formed and machined into the cylinders that will form the body of the Falcon 9 rocket just out of sight in front of you, or watch the complex circuitry of the flight hardware and avionics being inspected under a microscope to your left.

More than 80 percent of the Falcon rocket and Dragon spacecraft are built in-house. From the combustion chamber and nozzle at the bottom of the engine, to the capsule and its protective shield at the top. SpaceX designs and builds just about everything itself in a factory at the Hawthorne Airport where Jack Northrop built his legendary airplanes including flying wings and fighter jets. Just a handful of years ago, this same building was home to a factory making panels for Boeing 747s, today it is a self-contained space program hoping to make space flight as inexpensive and reliable as possible.

Photo: Jason Paur/Wired

A mezzanine above the factory floor offers the best view of SpaceX's Hawthorne facility. Nearly the entire factory can be seen here with the exception of the cafeteria and mission control which are just off the picture to the right, and the manufacturing and assembly area for the bigger items such as the large cylinders that make up the first and second stage of the Falcon 9 and the Dragon capsule, which are obscured by the clean room at top center and other infrastructure at top left.

Just about every major part of the entire SpaceX launch and orbital system is built in this one massive room.

Photo: Jason Paur/Wired

Several Dragon spacecraft have already been built. The first one to fly in orbit back in December 2010 sits near the middle of the factory. This spacecraft was the first to be launched by a private company into low earth orbit and recovered successfully. Before the flight of the Dragon pictured above, only Russia/Soviet Union, the United States and China had managed to perform such a mission.

The well-charred vehicle did get the attention of the Smithsonian Air & Space Museum. But the museum will have to wait. The capsule is still being used by the engineering team at SpaceX for testing and reference.

The Dragon is 12 feet (3.66 meters) in diameter at the base and inside the capsule there is a 350-cubic-foot (10 cubic meters) pressure vessel for cargo or up to seven astronauts. It can carry 7,297 pounds (3,310 kilograms) in its pressurized vessel and even more payload can be carried in an unpressurized trunk that is attached to the bottom on the way into orbit.

The heat shield at the bottom takes the brunt of the energy during re-entry reaching temperatures of 3,000 degrees Fahrenheit (1,649 Celsius). Made of a material called PICA developed first by NASA's Ames Research Center, the heat shield is an improvement over the tiles used by the space shuttle orbiters.

The ablative material on the sides of the Dragon does not have to withstand as much heat. The SpaceX logo on the top of the capsule is simply painted on and withstood the re-entry during flight (at least on this side of the capsule).

The Dragon uses 18 Draco thrusters to maneuver in orbit and to control the re-entry. The thrusters are able to burn for a millisecond or minutes depending on the need. Multiple propellant tanks can be cross-fed to any of the thrusters, creating a redundant system. Six of the Dracos are needed for re-entry and eventually SpaceX hopes to use an updated version of them to allow pinpoint landings on solid ground, rather than the ocean splashdown that will be used initially.

Photo: Jason Paur/Wired

The reusable Dragon first enters the SpaceX factory as sheets of aluminum. The sheets are are cut into sections and machined into the pieces seen here stacked near the charred Dragon. These will become the pressure vessel inside the capsule that is protected by the heat shield and covering. Temperatures inside can be kept at comfortable levels for passengers.

Photo: Jason Paur/Wired

Next the aluminum sheets are formed into the conic shape of the capsule and are welded together. Pictured above is what will become the Dragon capsule for the second commercial resupply mission to the ISS later this year.

Photo: Jason Paur/Wired

This is the back shell mold for the heat shield. Made of a metal called Invar, the structure is very resistant to dimensional change over a wide range of temperatures. Carbon fiber cloth and other composite pieces are laid in the mold and then baked at high temperatures to form the base of the capsule.

Photo: Jason Paur/Wired

Just to the left of middle, inside this clean room another Dragon pressure vessel can be seen as it is fitted with the red propellant tanks for the Draco thrusters. This capsule will become the Dragon spacecraft for the first commercial resupply mission to the ISS.

If SpaceX successfully completes the required demonstrations on the upcoming mission, the next two launches of the Falcon 9 and Dragon will be the two resupply missions to the station. In addition to satellite launches using just the Falcon 9, space station resupply missions three and four are scheduled for next year.

This is one of three clean rooms inside the factory. Each room has a different level of "clean" with the smallest and cleanest being used to assembling the thrusters.

Photo: Jason Paur/Wired

The all-important mission control isn't hidden in a back room at SpaceX. It's simply behind large glass walls to keep things relatively quiet during missions. "Instead of Houston, it's Hawthorne," is how SpaceX's Roger Gilbertson put it, referring to what is heard during communications between the various teams involved in the space missions. Though during the upcoming mission to the ISS, both Hawthorne and Houston will be working together closely.

Four large projectors turn the far wall into a giant desktop screen. Employees not directly involved in the operation of a mission can sit in the cafeteria or stand behind the glass and watch everything unfold right in front of them much like a movie. On the day of our visit, there was little going on inside mission control, but Hawthorne and Houston have rehearsed the entire mission several times ahead of tomorrow's launch.

Photo: Jason Paur/Wired

At the business end of the Falcon 9 are -- you guessed it -- nine Merlin rocket engines. Here a Merlin engine is being assembled. Visible on the near side of the engine is the shiny exhaust section beneath the turbopump. The turbopump is actually just a very high-powered fuel pump that feeds the main engine. The nozzle and bell-shaped combustion chamber have yet to be attached to this engine.

The turbopump not only feeds the RP-1 kerosene fuel to the rocket engine, it also provides the same high-pressure kerosene, which is also used as hydraulic fluid for steering the engines to control the Falcon 9. The nine Merlin engines will combine for more than 1 million pounds of thrust in vacuum and the booster can deliver its payload to orbit if any one engine fails at any time during the flight. The engine was developed internally at SpaceX but is based on a design first used on the lunar lander during the Apollo missions to the moon.

Photo: Jason Paur/Wired

Here workers move an engine nozzle. The nozzles are further machined before being attached to a completed Merlin engine.

Once assembled in Hawthorne, the rocket engines are transported to SpaceX's testing facility in Texas. There the engines are powered up and tested before returning to Hawthorne, where they are attached to the first and second stages of the Falcon 9.

Photo: Jason Paur/Wired

SpaceX builds several different rockets depending on the launch needs. At one end is the single engine Falcon 1 for lighter payloads to low earth orbit, at the other is the Falcon 9 for heavier LEO payloads. Pictured above is the Falcon 9.

Three of the nine complete Merlin engines are visible at the bottom. The burnished yellowish tube just to the left of center is the same turbopump exhaust assembly seen in the earlier photo. After testing, the metal is discolored.

The body of the Falcon rockets is made from aluminum-lithium sheets that are rolled at the factory to make half round sections. The sheets that make up the first stage of the rocket are only about 5 millimeters thick. A soda can scaled up to the same dimensions would be about twice as thick.The sections are then friction stir welded together. It takes about 10 days to assemble an entire first stage of the rocket fuselage.

Photo: Jason Paur/Wired

The secret payload from the first orbital mission of the Dragon spacecraft, a wheel of cheese, sits proudly -- and tightly sealed -- on the factory floor. During the December 2010 mission little was known about what might be on board the capsule. The cheese payload wasn't unveiled until after it had safely returned to earth.

In addition to fresh supplies of food, clothing and even a laptop, Saturday's launch will include several micro-gravity experiments from middle and high school students.

Photo: Jason Paur/Wired

There is a mixture of honoring space history along with science fiction throughout the SpaceX factory. Several rooms are named after historic figures such as Yuri Gagarin, the first person in space. Other rooms show the geeky side of the company such as Skynet, the artificial intelligence system that one day becomes self aware and next thing you know Arnold Schwarzenegger is terrorizing (or saving) Sarah Connor.

Photo: Jason Paur/Wired

After Saturday's early launch, the Dragon is expected to rendezvous and berth with the International Space Station sometime on Tuesday. The capsule is expected to stay attached to the ISS for a few weeks, returning to a splashdown in the Pacific Ocean some time in early June.